Simplify the following expression: $k = \dfrac{9}{5p} \div \dfrac{4}{7p}$
Solution: Dividing by an expression is the same as multiplying by its inverse. $k = \dfrac{9}{5p} \times \dfrac{7p}{4}$ When multiplying fractions, we multiply the numerators and the denominators. $k = \dfrac{ 9 \times 7p } { 5p \times 4}$ $k = \dfrac{63p}{20p}$ Simplify: $k = \dfrac{63}{20}$